1. Field of the Invention
The present invention relates generally to optical fiber, and more particularly to dispersion compensating optical fibers and systems including the same.
2. Technical Background
Increased demand for higher bit transmission rates has resulted in a large demand for optical transmission systems that can control and minimize dispersion effects. Analysis of common optical transmission systems indicates that while optical transmission systems can tolerate fairly large amounts of residual dispersion at 10 Gbit/second, these systems can tolerate only small amounts of residual dispersion at higher transmission rates of about 40 Gbit/second without causing unwanted signal distortion. Therefore, it is of the utmost importance to accurately control dispersion in such high bit-rate optical transmission systems across the entire wavelength band of interest.
In an attempt to address the need for fibers capable of transmission in dual windows (around 1310 and 1550 nm), new transmissions fibers have been developed having dispersion in the range from about 5 to 14 ps/nm/km at 1550 nm. These so-called moderate dispersion Non-Zero Dispersion Shifted Fibers (NZDSF) preferably have dispersion slopes less than about 0.08 ps/nm2/km at 1550 nm; more preferably in the range of about 0.035 to 0.07 ps/nm2/km at 1550 nm. Further, they preferably exhibit effective areas at 1550 nm of greater than about 45 μm2, more preferably between about 50 and 75 μm2 at 1550 nm, and have λo between about 1300 and 1480 nm.
Thus, there is a need for a dispersion compensating fiber useful for compensating accumulated dispersion in spans including such moderate dispersion NZDSF.